Rear portion of a motorcycle



FIG. 1 is a front elevation view of a rear portion of a motorcycle, showing our new design;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a perspective view thereof;

FIG. 7 is an enlarged front elevation view thereof;

FIG. 8 is an enlarged right side elevation view thereof; and,

FIG. 9 is an enlarged perspective view thereof.

The pattern of longer and shorter broken lines define the boundaries of the claimed rear portion of a motorcycle and form no part of the claimed design, while the other broken lines show the environment of the rear portion of a motorcycle and form no part of the claimed design. 

The ornamental design for, a rear portion of a motorcycle, as shown and described. 